Thelohanellus habibpuri sp. n. (Myxozoa: Bivalvulida) from the tropical freshwater fish rohu, Labeo rohita (Hamilton-Buchanan, 1882) in West Bengal, India: Light and electron microscope observations

Abstract

AbstractA new species of myxozoan (Myxozoa: Bivalvulida) Thelohanellus habibpuri sp. n. parasitic in tropical freshwater fish collected from the Habibpur, West Bengal, India is described in this paper. T. habibpuri was found in the Pectoral fin of Labeo rohita (Hamilton-Buchanan, 1882). The diagnostic characters of T. habibpuri are: generally oval milky-whitish plasmodia attached in the pectoral fin of host fishes; spore egg-shaped to ovoid with slightly tapering anterior and rounded posterior end, averaging 13.9 × 8.5 μm in size; a single oval-round polar capsule 6.0 × 4.9 μm in diameter, with polar filament wound in 3-4 coils. Finely granular sporoplasm containing two slightly oval nuclei (1.4 μm in diameter) and a small iodinophilous vacuole (3.0 μm in diameter) present in the spore.SEM study of this myxozoan reveals the anterior extremity of spore is truncated. The Cnidocyst discharge channel appear as a dark area. The longitudinal wavy surface are visible on the spore.